It is generally believed that all biological functions can be interpreted on a molecular level and that there exists a structure-function relationship. The proposed work is to study the conformation of proteins and polypeptides by means of circular dichroism (CD) and optical rotatory dispersion (ORD) together with other physicochemical methods. The CD analysis of protein conformation has been developed in this laboratory. It enables us to estimate the percentages of helix, Beta-form, and Beta-turns in a protein molecule. The method is now applied to a few chosen proteins and polypeptides such as muscle proteins and hormones from pancreas. Relative changes in conformation that accompany denaturation will be followed by the changes in CD spectra. The effect of surfactants on protein conformation will also be studied in order to gain a better understanding of the hydrophobic interactions of these compounds with respect to protein conformation that play an important role in membrane proteins and lipoproteins. BIBLIOGRAPHIC REFERENCES: Tseng, Y.W. & Yang, J.T. (1977) Conformation of Poly(L-lysine) Homologs in Solution. Biopolymers, in press. Chen, Y.H., Lo, T.B. & Yang, J.T. (1977) Optical Activity and Conformation of Cobra Neurotoxin. Biochemistry, in press.